Tape cassette, in particular a video tape cassette, and a pressure spring therefor

Abstract

A transparent window member for a tape cassette, which together with a reel pressure spring, forms a subassembly of the cassette. The reel pressure spring has a U-shaped central portion, the bight of the U being parallel to the plane of the spring arms, and the reel pressure spring having a longitudinal edge with two transverse slits spaced the same as the legs of the U of the central portion of the pressure spring. The central portion may thus be transversely inserted in the longitudinal edge of the window member and it thus forms a locating element for the pressure spring.

We claim: 
     
       1. A tape cassette having a housing with a top and a bottom, a pair of tape reels and a reel pressure spring attachable to said top for urging said reels in the direction of the bottom of the housing, said reel pressure spring having two arms extending from a central portion of the spring, which portion projects away from the plane of the spring arms and is in the shape of a U having a bite portion parallel to said plane and two upstanding leg portions, and the top of said housing comprising   a holding means for said reel pressure spring, said holding means being in the form of a transparent window member and having a longitudinal edge with two transversely extending slits therein, said slits having a mutual spacing the same as that of the legs of the U-shaped central portion of the spring,   so that said central portion of the reel pressure spring, which forms a locating means, may be transversely inserted into the longitudinal edge of said transparent window member, said window member and the spring upon insertion therein forming a subassembly.   
     
     
       2. A tape cassette as claimed in claim 1, wherein said window memeber has between said slits a recessed ledge portion upon which said bite portion rests upon insertion of the central portion of said spring. 
     
     
       3. A transparent window member for a tape cassette having a housing with a top to which said window member is attachable, a bottom, a pair of tape reels and a reel pressure spring mountable on said window member for urging said reels in the direction of the bottom of the housing, said reel pressure spring having two arms extending from a central portion of the spring which portion projects away from the plane of the spring arms and is in the shape of a U having a bite portion parallel to said plane and two upstanding leg portions, said window member having a longitudinal edge with two transversely extending slits therein, said slits having a mutual spacing the same as that of the legs of the U-shaped central portion of the spring,   so that said central portion of the reel pressure spring, which forms a locating means, may be transversely inserted into the longitudinal edge of said window member, said window member and said reel pressure spring upon insertion into the window member forming together a subassembly of said tape cassette.   
     
     
       4. A window member as claimed in claim 3, wherein said window member has between said slits a recessed ledge portion upon which said bite portion rests upon insertion of the central portion of said spring, the window member and the spring upon insertion forming a subassembly. 
     
     
       5. A window member as claimed in claim 4, wherein said ledge portion is recessed from the upper face of said window member by an amount the same as or greater than the thickness of said bite portion of the spring. 
     
     
       6. A window member as claimed in claim 4, wherein said window member has a welding edge for welding said subassembly to the housing top. 
     
     
       7. A window member as claimed in claim 6, wherein said welding edge, in the area of said recessed ledge portion, extends closely around the major part of the contour of said ledge portion so as to insure that the reel pressure spring in the area of its central portion is tightly clamped against the housing top. 
     
     
       8. A window member as claimed in claim 6, wherein along the outer edge of said recessed ledge portion a raised rib is formed to prevent the spring from falling out prior to the welding of the subassembly to the housing top. 
     
     
       9. A transparent-window-member/reel-pressure-spring subassembly for a tape cassette having a housing with a top to which said window member is attachable, a bottom and a pair of tape reels, said reel pressure spring being mountable on said window member for urging said reels in the direction of the bottom of the housing, said reel pressure spring having two arms extending from a central portion of the spring which portion projects away from the plane of the spring arms and is in the shape of a U having a bite portion parallel to said plane and two upstanding leg portions, said window member having a longitudinal edge with two transversely extending slits therein, said slits having a mutual spacing the same as that of the legs of the U-shaped central portion of the spring,   so that said central portion of the reel pressure spring, which forms a locating means, may be transversely inserted into the longitudinal edge of said window member to for said subassembly.